Fig. 5. Alignment of HsNHA genes. Sequence alignment of human NHA1 and NHA2 showing regions of identity (black boxes; 55%) and similarity (gray boxes; 69%) over 515 amino acids.

Fig. 6. Quinidine inhibits NHA2-mediated Li⁺ tolerance. Quinidine was added to yeast cultures at the concentrations indicated. Yeast strains expressing NHA2 or DD®CC mutant were grown in APG pH 4 medium in the absence or presence of 25 mM LiCl as indicated by the line above the graphs. Dose-dependent inhibition of salt-tolerant growth was seen in NHA2 transformed cells, however, quinidine did not inhibit growth in the absence of LiCl (1 mM; last bar).